SOFOSBUVIR: 17,291 Adverse Event Reports & Safety Profile

VOSEVI is a fixed-dose combination tablet containing sofosbuvir, velpatasvir, and voxilaprevir for oral administration. Sofosbuvir is a nucleotide analog HCV NS5B polymerase inhibitor, velpatasvir is an NS5A inhibitor, and voxilaprevir is an NS3/4A protease inhibitor. Each tablet contains 400 mg sofosbuvir, 100 mg velpatasvir, and 100 mg of voxilaprevir. The tablets include the following inactive ingredients: colloidal silicon dioxide, copovidone, croscarmellose sodium, lactose monohydrate, magnesium stearate, and microcrystalline cellulose. The tablets are film-coated with a coating material containing the following inactive ingredients: ferrosoferric oxide, iron oxide red, iron oxide yellow, polyethylene glycol, polyvinyl alcohol, talc, and titanium dioxide. Sofosbuvir: The IUPAC name for sofosbuvir is ( S )-Isopropyl 2-(( S )-(((2 R ,3 R ,4 R ,5 R )-5-(2,4-dioxo-3,4-dihydropyrimidin-1(2 H )-yl)-4-fluoro-3-hydroxy-4-methyltetrahydrofuran-2-yl)methoxy)-(phenoxy)phosphorylamino)propanoate. It has a molecular formula of C 22 H 29 FN 3 O 9 P and a molecular weight of 529.45. It has the following structural formula: Sofosbuvir is a white to off-white crystalline solid with a solubility of at least 2 mg/mL across the pH range of 2–7.7 at 37 °C and is slightly soluble in water.

Chemical Structure

Velpatasvir: The IUPAC name for velpatasvir is Methyl {(1 R )-2-[(2 S ,4 S )-2-(5-{2-[(2 S ,5 S )-1-{(2 S )-2-[(methoxycarbonyl)amino]-3-methylbutanoyl}-5-methylpyrrolidin-2-yl]-1,11-dihydro[2]benzopyrano[4',3':6,7]naphtho[1,2- d ]imidazol-9-yl}-1 H -imidazol-2-yl)-4-(methoxymethyl)pyrrolidin-1-yl]-2-oxo-1-phenylethyl}carbamate. It has a molecular formula of C 49 H 54 N 8 O 8 and a molecular weight of 883.0. It has the following structural formula: Velpatasvir is practically insoluble (less than 0.1 mg/mL) above pH 5, slightly soluble (3.6 mg/mL) at pH 2, and soluble (greater than 36 mg/mL) at pH 1.2.

Chemical Structure

Voxilaprevir: The IUPAC name for voxilaprevir is (1 aR ,5 S ,8 S ,9 S ,10 R ,22a R )-5- tert -butyl- N -{(1 R ,2 R )-2-(difluoromethyl)-1-[(1-methylcyclopropanesulfonyl) carbamoyl]cyclopropyl}-9-ethyl-18,18-difluoro-14-methoxy-3,6-dioxo-1,1 a ,3,4,5,6,9,10,18,19,20,21,22,22 a -tetradecahydro-8 H -7,10-methanocyclopropa[18,19][1,10,3,6]dioxadiazacyclononadecino[11,12- b ]quinoxaline-8-carboxamide. It has a molecular formula of C 40 H 52 F 4 N 6 O 9 S and a molecular weight of 868.9. It has the following structural formula: Voxilaprevir is a white to light brown solid. It is slightly hygroscopic to hygroscopic. Voxilaprevir is practically insoluble (less than 0.1 mg/mL) below pH 6.8.

Chemical

Structure

AND USAGE VOSEVI is indicated for the treatment of adult patients with chronic hepatitis C virus (HCV) infection without cirrhosis or with compensated cirrhosis (Child-Pugh A) who have [see Dosage and Administration (2.2) and Clinical Studies (14) ]: genotype 1, 2, 3, 4, 5, or 6 infection and have previously been treated with an HCV regimen containing an NS5A inhibitor. genotype 1a or 3 infection and have previously been treated with an HCV regimen containing sofosbuvir without an NS5A inhibitor. Additional benefit of VOSEVI over sofosbuvir/velpatasvir was not shown in adults with genotype 1b, 2, 4, 5, or 6 infection previously treated with sofosbuvir without an NS5A inhibitor. VOSEVI is a fixed-dose combination of sofosbuvir, a hepatitis C virus (HCV) nucleotide analog NS5B polymerase inhibitor, velpatasvir, an HCV NS5A inhibitor, and voxilaprevir, an HCV NS3/4A protease inhibitor, and is indicated for the treatment of adult patients with chronic HCV infection without cirrhosis or with compensated cirrhosis (Child-Pugh A) who have ( 1 , 2.2 , 14 ): genotype 1, 2, 3, 4, 5, or 6 infection and have previously been treated with an HCV regimen containing an NS5A inhibitor. genotype 1a or 3 infection and have previously been treated with an HCV regimen containing sofosbuvir without an NS5A inhibitor. Additional benefit of VOSEVI over sofosbuvir/velpatasvir was not shown in adults with genotype 1b, 2, 4, 5, or 6 infection previously treated with sofosbuvir without an NS5A inhibitor.

AND ADMINISTRATION Testing Prior to the Initiation of Therapy: Test all patients for HBV infection by measuring HBsAg and anti-HBc. ( 2.1 ) Recommended dosage in adults: One 400 mg tablet taken once daily with or without food. ( 2.2 ) Recommended dosage in pediatric patients 3 years of age and older: Recommended dosage of SOVALDI in pediatric patients 3 years of age and older with genotype 2 or 3 HCV using SOVALDI tablets or oral pellets is based on weight. Refer to Table 3 of the full prescribing information for specific dosing guidelines based on body weight. ( 2.3 ) HCV/HIV-1 coinfection: For adult and pediatric patients with HCV/HIV-1 coinfection, follow the dosage recommendations in the tables below, respectively. ( 2.2 , 2.3 ) Recommended adult treatment regimen and duration: ( 2.2 )

Adult Patient Population

Regimen and Duration Genotype 1 or 4 Treatment-naïve without cirrhosis or with compensated cirrhosis (Child-Pugh A) SOVALDI + peginterferon alfa + ribavirin 12 weeks Genotype 2 Treatment-naïve and treatment-experienced without cirrhosis or with compensated cirrhosis (Child-Pugh A) SOVALDI + ribavirin 12 weeks Genotype 3 Treatment-naïve and treatment-experienced without cirrhosis or with compensated cirrhosis (Child-Pugh A) SOVALDI + ribavirin 24 weeks SOVALDI in combination with ribavirin for 24 weeks can be considered for adult patients with genotype 1 infection who are interferon ineligible. ( 2.2 ) Should be used in combination with ribavirin for treatment of HCV in adult patients with hepatocellular carcinoma awaiting liver transplantation for up to 48 weeks or until liver transplantation, whichever occurs first. ( 2.2 ) Recommended treatment regimen and duration for pediatric patients 3 years of age and older: ( 2.3 , 2.4 )

Pediatric Patient Population

3 Years of Age and Older Regimen and Duration Genotype 2 Treatment-naïve and treatment-experienced without cirrhosis or with compensated cirrhosis (Child-Pugh A) SOVALDI + ribavirin 12 weeks Genotype 3 Treatment-naïve and treatment-experienced without cirrhosis or with compensated cirrhosis (Child-Pugh A) SOVALDI + ribavirin 24 weeks A dosage recommendation cannot be made for patients with severe renal impairment or end stage renal disease. ( 2.7 , 8.6 ) Instructions for Use should be followed for preparation and administration of SOVALDI oral pellets. ( 2.4 )

2.1 Testing Prior to the Initiation of Therapy Test all patients for evidence of current or prior HBV infection by measuring hepatitis B surface antigen (HBsAg) and hepatitis B core antibody (anti-HBc) before initiating HCV treatment with SOVALDI <span class="opacity-50 text-xs">[see Warnings and Precautions (5.1)]</span> .

2.2 Recommended Dosage in Adults The recommended dosage of SOVALDI is one 400 mg tablet, taken orally, once daily with or without food <span class="opacity-50 text-xs">[see Clinical Pharmacology (12.3) ]</span> . Administer SOVALDI in combination with ribavirin or in combination with pegylated interferon and ribavirin for the treatment of HCV. The recommended treatment regimen and duration for SOVALDI combination therapy is provided in Table 1. For patients with HCV/HIV-1 coinfection, follow the dosage recommendations in Table 1. Refer to Drug Interactions (7) for dosage recommendations for concomitant HIV-1 antiviral drugs.

Table

1 Recommended Treatment Regimen and Duration in Adult Patients with Genotype 1, 2, 3, or 4 HCV Patient Population Treatment Regimen and Duration Genotype 1 or 4 Treatment-naïve without cirrhosis or with compensated cirrhosis (Child-Pugh A) SOVALDI + peginterferon alfa See peginterferon alfa prescribing information for dosage recommendation for patients with genotype 1 or 4 HCV. + ribavirin Dosage of ribavirin is weight-based (<75 kg = 1000 mg and ≥75 kg = 1200 mg). The daily dosage of ribavirin is administered orally in two divided doses with food. Patients with renal impairment (CrCl ≤50 mL/min) require ribavirin dosage reduction; refer to ribavirin tablet prescribing information. 12 weeks Genotype 2 Treatment-naïve and treatment-experienced Treatment-experienced patients have failed an interferon-based regimen with or without ribavirin. without cirrhosis or with compensated cirrhosis (Child-Pugh A) SOVALDI + ribavirin 12 weeks Genotype 3 Treatment-naïve and treatment-experienced without cirrhosis or with compensated cirrhosis (Child-Pugh A) SOVALDI + ribavirin 24 weeks Patients with Genotype 1 HCV Who are Ineligible to Receive an Interferon-Based Regimen SOVALDI in combination with ribavirin for 24 weeks can be considered as a therapeutic option for patients with genotype 1 infection who are ineligible to receive an interferon-based regimen [see Clinical Studies (14.4) ] . Treatment decision should be guided by an assessment of the potential benefits and risks for the individual patient. Patients with Hepatocellular Carcinoma Awaiting Liver Transplantation Administer SOVALDI in combination with ribavirin for up to 48 weeks or until the time of liver transplantation, whichever occurs first, to prevent post-transplant HCV reinfection [see Use in Specific Populations (8.8) ] .

2.3 Recommended Dosage in Pediatric Patients 3 Years of Age and Older with Genotype 2 or 3 HCV The recommended treatment regimen, duration, and recommended dosage for SOVALDI combination therapy is provided in Table 2 and Table 3.

Table

4 provides the weight-based dosage of ribavirin when used in combination with SOVALDI for pediatric patients. For patients with HCV/HIV-1 coinfection, follow the dosage recommendations in Table 3 and Table 4. Refer to Drug Interactions (7) for dosage recommendations for concomitant HIV-1 antiviral drugs. In pediatric patients with hepatocellular carcinoma awaiting liver transplantation, administer SOVALDI in combination with ribavirin for up to 48 weeks or until the time of liver transplantation, whichever occurs first, to prevent post-transplant HCV reinfection [see Use in Specific Populations (8.8) ] .

Table

2 Recommended Treatment Regimen and Duration in Pediatric Patients 3 Years and Older with Genotype 2 or 3 HCV Patient Population Treatment Regimen and Duration Genotype 2 Treatment-naïve and treatment-experienced Treatment-experienced patients have failed an interferon based regimen with or without ribavirin. without cirrhosis or with compensated cirrhosis (Child-Pugh A) SOVALDI + ribavirin See Table 4 for weight-based ribavirin dosing recommendations. 12 weeks Genotype 3 Treatment-naïve and treatment-experienced without cirrhosis or with compensated cirrhosis (Child-Pugh A) SOVALDI + ribavirin 24 weeks The recommended dosage of SOVALDI in pediatric patients 3 years and older with genotype 2 or 3 HCV using SOVALDI tablets or oral pellets (with or without food) is based on weight (Table 3), and is to be taken orally once daily in combination with ribavirin [see Dosage and Administration (2.4) , Use in Specific Populations (8.4) , Clinical Pharmacology (12.3) , and Clinical Studies (14.5) ] . SOVALDI pellets can be taken by pediatric patients who cannot swallow the tablet formulation [see Dosage and Administration (2.4) ] .

Table

3 Dosing for Pediatric Patients 3 Years and Older Using SOVALDI Tablets or Oral Pellets Body Weight (kg) Dosing of SOVALDI Tablets or Oral Pellets SOVALDI Daily Dose at least 35 one 400 mg tablet once daily or two 200 mg tablets once daily or two 200 mg packets of pellets once daily 400 mg per day 17 to less than 35 one 200 mg tablet once daily or one 200 mg packet of pellets once daily 200 mg per day less than 17 one 150 mg packet of pellets once daily 150 mg per day Table 4 Recommended Dosing for Ribavirin in Combination Therapy with SOVALDI for Pediatric Patients 3 Years and Older Body Weight (kg)

Oral Ribavirin Daily Dosage

The daily dosage of ribavirin is weight-based and is administered orally in two divided doses with food. less than 47 15 mg per kg per day (divided dose AM and PM) 47–49 600 mg per day (1 × 200 mg AM, 2 × 200 mg PM) 50–65 800 mg per day (2 × 200 mg AM, 2 × 200 mg PM) 66–80 1000 mg per day (2 × 200 mg AM, 3 × 200 mg PM) greater than 80 1200 mg per day (3 × 200 mg AM, 3 × 200 mg PM)

2.4 Preparation and Administration of Oral Pellets See the SOVALDI oral pellets full Instructions for Use for details on the preparation and administration of SOVALDI pellets. Do not chew SOVALDI pellets. If SOVALDI pellets are administered with food, sprinkle the pellets on one or more spoonfuls of non-acidic soft food at or below room temperature. Examples of non-acidic foods include pudding, chocolate syrup, mashed potato, and ice cream. Take SOVALDI pellets within 30 minutes of gently mixing with food and swallow the entire contents without chewing to avoid a bitter aftertaste.

2.5 Dosage Modification Dosage reduction of SOVALDI is not recommended. If a patient has a serious adverse reaction potentially related to peginterferon alfa and/or ribavirin, the peginterferon alfa and/or ribavirin dosage should be reduced or discontinued, if appropriate, until the adverse reaction abates or decreases in severity. Refer to the peginterferon alfa and ribavirin prescribing information for additional information about how to reduce and/or discontinue the peginterferon alfa and/or ribavirin dosage.

2.6 Discontinuation of Dosing If the other agents used in combination with SOVALDI are permanently discontinued, SOVALDI should also be discontinued.

2.7 Severe Renal Impairment and End Stage Renal Disease No dosage recommendation can be given for patients with severe renal impairment (estimated Glomerular Filtration Rate [eGFR] less than 30 mL/min/1.73m 2 ) or with end stage renal disease (ESRD) due to higher exposures (up to 20-fold) of the predominant sofosbuvir metabolite <span class="opacity-50 text-xs">[see Use in Specific Populations (8.6) and Clinical Pharmacology (12.3) ]</span> .

When SOVALDI is used in combination with ribavirin or peginterferon alfa/ribavirin, the contraindications applicable to those agents are applicable to combination therapies. Refer to the prescribing information of peginterferon alfa and ribavirin for a list of their contraindications. When used in combination with peginterferon alfa/ribavirin or ribavirin alone, all contraindications to peginterferon alfa and/or ribavirin also apply to SOVALDI combination therapy. ( 4 )

REACTIONS The following serious adverse reactions are described below and elsewhere in labeling: Serious Symptomatic Bradycardia When Coadministered with Amiodarone [see Warnings and Precautions (5.2) ]. The most common adverse reactions (incidence greater than or equal to 10%, all grades) observed in adults and pediatric subjects 6 years of age and older with treatment with sofosbuvir and velpatasvir for 12 weeks are headache and fatigue. ( 6.1 ) The most common adverse reactions (incidence greater than or equal to 10%, grade 1 or 2) observed in pediatric subjects less than 6 years of age are vomiting and product use issue (spitting up the drug). ( 6.1 ) The most common adverse reactions (incidence greater than or equal to 10%, all grades) observed with treatment with sofosbuvir and velpatasvir and ribavirin for 12 weeks in adult patients with decompensated cirrhosis are fatigue, anemia, nausea, headache, insomnia, and diarrhea. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Asegua Therapeutics at 1-800-445-3235 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.

6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. If sofosbuvir and velpatasvir is administered with ribavirin, refer to the prescribing information for ribavirin for a description of ribavirin-associated adverse reactions.

Clinical

Trials in Adult Subjects Adverse Reactions in Subjects without Cirrhosis or with Compensated Cirrhosis The adverse reactions data for sofosbuvir and velpatasvir in patients without cirrhosis or with compensated cirrhosis were derived from three Phase 3 clinical trials (ASTRAL-1, ASTRAL-2, and ASTRAL-3) which evaluated a total of 1035 subjects infected with genotype 1, 2, 3, 4, 5, or 6 HCV, without cirrhosis or with compensated cirrhosis, who received sofosbuvir and velpatasvir tablets (400 mg/100 mg) for 12 weeks. Sofosbuvir and velpatasvir were studied in placebo- and active-controlled trials [see Clinical Studies (14.2) ] . The proportion of subjects who permanently discontinued treatment due to adverse events was 0.2% for subjects who received sofosbuvir and velpatasvir for 12 weeks. The most common adverse reactions (adverse events assessed as causally related by the investigator and at least 10%) were headache and fatigue in subjects treated with sofosbuvir and velpatasvir for 12 weeks. Adverse reactions, all grades, observed in greater than or equal to 5% of subjects receiving 12 weeks of treatment with sofosbuvir and velpatasvir in ASTRAL-1 include headache (22%), fatigue (15%), nausea (9%), asthenia (5%), and insomnia (5%). Of subjects receiving sofosbuvir and velpatasvir who experienced these adverse reactions, 79% had an adverse reaction of mild severity (Grade 1). With the exception of asthenia, each of these adverse reactions occurred at a similar frequency or more frequently in subjects treated with placebo compared to subjects treated with sofosbuvir and velpatasvir (asthenia: 3% versus 5% for the placebo and sofosbuvir and velpatasvir groups, respectively). The adverse reactions observed in subjects treated with sofosbuvir and velpatasvir in ASTRAL-2 and ASTRAL-3 were consistent with those observed in ASTRAL-1. Irritability was also observed in greater than or equal to 5% of subjects treated with sofosbuvir and velpatasvir in ASTRAL-3.

Adverse

Reactions in Subjects Coinfected with HCV and HIV-1 The safety assessment of sofosbuvir and velpatasvir in subjects with HCV/HIV-1 coinfection was based on an open-label clinical trial (ASTRAL-5) in 106 subjects who were on stable antiretroviral therapy [see Clinical Studies (14.3) ] . The safety profile in HCV/HIV-1 coinfected subjects was similar to that observed in HCV mono-infected subjects. The most common adverse reactions occurring in at least 10% of subjects were fatigue (22%) and headache (10%).

Adverse

Reactions in Subjects with Decompensated Cirrhosis The safety assessment of sofosbuvir and velpatasvir in subjects infected with genotype 1, 2, 3, 4, or 6 HCV with decompensated cirrhosis was based on one Phase 3 trial (ASTRAL-4) including 87 subjects who received sofosbuvir and velpatasvir tablets (400 mg/100 mg) with ribavirin for 12 weeks.

All

87 subjects had Child-Pugh B cirrhosis at screening. On the first day of treatment with sofosbuvir and velpatasvir with ribavirin, 6 subjects and 4 subjects were assessed to have Child-Pugh A and Child-Pugh C cirrhosis, respectively [see Clinical Studies (14.4) ] . The most common adverse reactions (adverse events assessed as causally related by the investigator, all grades with frequency of 10% or greater) in the 87 subjects who received sofosbuvir and velpatasvir with ribavirin for 12 weeks were fatigue (32%), anemia (26%), nausea (15%), headache (11%), insomnia (11%), and diarrhea (10%). Of subjects who experienced these adverse reactions, 98% had adverse reactions of mild to moderate severity. A total of 4 (5%) subjects permanently discontinued sofosbuvir and velpatasvir with ribavirin due to an adverse event; there was no adverse event leading to discontinuation that occurred in more than 1 subject. Decreases in hemoglobin to less than 10 g/dL and 8.5 g/dL during treatment were observed in 23% and 7% of subjects treated with sofosbuvir and velpatasvir with ribavirin for 12 weeks, respectively. Ribavirin was permanently discontinued in 17% of subjects treated with sofosbuvir and velpatasvir with ribavirin for 12 weeks, due to adverse reactions.

Less Common Adverse Reactions

Reported in Clinical Trials The following adverse reactions occurred in less than 5% of subjects without cirrhosis or with compensated cirrhosis treated with sofosbuvir and velpatasvir tablets (400 mg/100 mg) for 12 weeks and are included because of a potential causal relationship. Rash: In the ASTRAL-1 study, rash occurred in 2% of subjects treated with sofosbuvir and velpatasvir and in 1% of subjects treated with placebo. No serious adverse reactions of rash occurred, and all rashes were mild or moderate in severity. Depression: In the ASTRAL-1 study, depressed mood occurred in 1% of subjects treated with sofosbuvir and velpatasvir and was not reported by any subject taking placebo. No serious adverse reactions of depressed mood occurred, and all events were mild or moderate in severity. The following adverse reactions occurred in less than 10% of subjects with decompensated cirrhosis (ASTRAL-4) treated with sofosbuvir and velpatasvir with ribavirin for 12 weeks and are included because of a potential causal relationship. Rash: Rash occurred in 5% of subjects treated with sofosbuvir and velpatasvir with ribavirin. No serious adverse reactions of rash occurred, and all rashes were mild or moderate in severity.

Laboratory Abnormalities Lipase

Elevations: In ASTRAL-1, isolated, asymptomatic lipase elevations of greater than 3×ULN were observed in 3% and 1% of subjects treated with sofosbuvir and velpatasvir tablets (400 mg/100 mg) and placebo for 12 weeks, respectively; and in 6% and 3% of subjects treated with sofosbuvir and velpatasvir tablets (400 mg/100 mg) in ASTRAL-2 and ASTRAL-3, respectively. In the Phase 3 trial of subjects with decompensated cirrhosis (ASTRAL-4), lipase was assessed when amylase values were greater than or equal to 1.5×ULN. Isolated, asymptomatic lipase elevations of greater than 3×ULN were observed in 2% of subjects treated with sofosbuvir and velpatasvir tablets (400 mg/100 mg) with ribavirin for 12 weeks.

Creatine

Kinase: In ASTRAL-1, isolated, asymptomatic creatine kinase elevations greater than or equal to 10×ULN were reported in 1% and 0% of subjects treated with sofosbuvir and velpatasvir tablets (400 mg/100 mg) and placebo for 12 weeks, respectively; and in 2% and 1% of subjects treated with sofosbuvir and velpatasvir tablets (400 mg/100 mg) in ASTRAL-2 and ASTRAL-3, respectively. In the Phase 3 trial with decompensated cirrhosis (ASTRAL-4), isolated, asymptomatic creatine kinase elevations greater than or equal to 10×ULN were reported in 1% of subjects treated with sofosbuvir and velpatasvir tablets (400 mg/100 mg) with ribavirin for 12 weeks.

Indirect

Bilirubin: Increases in indirect bilirubin up to 3 mg/dL above baseline were noted among HIV-1/HCV coinfected subjects treated with sofosbuvir and velpatasvir and an atazanavir/ritonavir-based antiretroviral regimen. The elevated indirect bilirubin values were not associated with clinical adverse events, and all subjects completed 12 weeks of sofosbuvir and velpatasvir without dose adjustment or treatment interruption of either sofosbuvir and velpatasvir or HIV antiretroviral agents.

Adverse

Reactions in Adult Liver Transplant Recipients The safety assessment of sofosbuvir and velpatasvir in liver transplant recipients was based on an open-label clinical trial (Trial 2104) in 79 adults without cirrhosis or with compensated cirrhosis who received sofosbuvir and velpatasvir tablets (400 mg/100 mg) for 12 weeks [see Clinical Studies (14.5) ] . One subject discontinued treatment due to an adverse event on Day 7. The adverse reactions observed were consistent with the known safety profile of sofosbuvir and velpatasvir. Adverse reactions occurring in at least 5% of subjects were headache (18%), fatigue (15%), nausea (8%), diarrhea (6%), and asthenia (5%).

Adverse

Reactions in Adults with Severe Renal Impairment Requiring Dialysis In an open-label trial (Trial 4062), in which a total of 59 adults with HCV with compensated liver disease (with or without cirrhosis) and ESRD requiring dialysis received sofosbuvir and velpatasvir tablets (400 mg/100 mg) for 12 weeks, the most common adverse reaction was nausea (7%) [see Clinical Studies (14.6) ].

Adverse

Reactions in People Who Inject Drugs (PWID), Including Those on Medication-Assisted Treatment (MAT) for Opioid Use Disorder The safety of sofosbuvir and velpatasvir in PWID is based on an open-label Phase 2 trial (SIMPLIFY) that enrolled 103 adult subjects with chronic HCV genotype 1, 2, 3, and 4 infection. Subjects who self-reported injection drug use within the 6 months prior to starting treatment were eligible and were treated with sofosbuvir and velpatasvir tablets (400 mg/100 mg) for 12 weeks. The trial included a subset of 58 subjects on MAT for opioid use disorder. The adverse reactions observed from SIMPLIFY both overall and in subjects on MAT were consistent with the known safety profile of sofosbuvir and velpatasvir. The most common adverse reactions overall were fatigue (18%), nausea (13%), and headache (11%) [see Use in Specific Populations (8.8) and Clinical Studies (14.7) ]. Adverse reactions leading to permanent discontinuation of treatment were not observed in any subjects.

Adverse

Reactions in Pediatric Subjects 3 Years of Age and Older The safety assessment of sofosbuvir and velpatasvir tablets (400 mg/100 mg), sofosbuvir and velpatasvir (EPCLUSA) tablets (200 mg/50 mg), or sofosbuvir and velpatasvir (EPCLUSA) oral pellets in pediatric subjects 3 years of age and older is based on data from a Phase 2, open-label clinical trial (Study 1143) that enrolled 216 subjects who were treated with sofosbuvir and velpatasvir for 12 weeks [see Clinical Studies (14.8) ]. The adverse reactions observed in pediatric subjects 6 years of age and older were consistent with those observed in clinical trials of sofosbuvir and velpatasvir tablets (400 mg/100 mg) in adults. Among the 41 pediatric subjects less than 6 years of age, gastrointestinal adverse reactions were reported more commonly compared to subjects 6 years of age and older. Vomiting and product use issue (spitting up the drug) were reported in 15% and 10% of subjects, respectively; these adverse reactions were mild (Grade 1 or 2) and led to treatment discontinuation in 5 (12%) subjects [see Use in Specific Populations (8.4) and Clinical Studies (14.8) ].

6.2 Postmarketing Experience The following adverse reactions have been identified during post approval use of sofosbuvir. Because postmarketing reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure.

Cardiac Disorders

Serious symptomatic bradycardia has been reported in patients taking amiodarone who initiate treatment with a sofosbuvir-containing regimen [see Warnings and Precautions (5.2) and Drug Interactions (7.3) ]. Skin and Subcutaneous Tissue Disorders Skin rashes, sometimes with blisters or angioedema-like swelling Angioedema

AND PRECAUTIONS Risk of Hepatitis B Virus Reactivation: Test all patients for evidence of current or prior HBV infection before initiation of HCV treatment. Monitor HCV/HBV coinfected patients for HBV reactivation and hepatitis flare during HCV treatment and post-treatment follow-up. Initiate appropriate patient management for HBV infection as clinically indicated. ( 5.1 ) Risk of Hepatic Decompensation/Failure in Patients with Evidence of Advanced Liver Disease: Hepatic decompensation/failure, including fatal outcomes, have been reported mostly in patients with cirrhosis and baseline moderate or severe liver impairment (Child-Pugh B or C) treated with HCV NS3/4A protease inhibitor-containing regimens. Monitor for clinical and laboratory evidence of hepatic decompensation. Discontinue VOSEVI in patients who develop evidence of hepatic decompensation/failure. ( 5.2 ) Bradycardia with Amiodarone Coadministration: Serious symptomatic bradycardia may occur in patients taking amiodarone with VOSEVI, a sofosbuvir-containing regimen, particularly in patients also receiving beta blockers, or those with underlying cardiac comorbidities and/or advanced liver disease. Coadministration of amiodarone with VOSEVI is not recommended. In patients without alternative viable treatment options, cardiac monitoring is recommended. ( 5.3 , 7.3 )

5.1 Risk of Hepatitis B Virus Reactivation in Patients Coinfected with HCV and HBV Hepatitis B virus (HBV) reactivation has been reported in HCV/HBV coinfected patients who were undergoing or had completed treatment with HCV direct-acting antivirals, and who were not receiving HBV antiviral therapy. Some cases have resulted in fulminant hepatitis, hepatic failure, and death. Cases have been reported in patients who are HBsAg positive and also in patients with serologic evidence of resolved HBV infection (i.e., HBsAg negative and anti-HBc positive). HBV reactivation has also been reported in patients receiving certain immunosuppressant or chemotherapeutic agents; the risk of HBV reactivation associated with treatment with HCV direct-acting antivirals may be increased in these patients. HBV reactivation is characterized as an abrupt increase in HBV replication manifesting as a rapid increase in serum HBV DNA level. In patients with resolved HBV infection reappearance of HBsAg can occur. Reactivation of HBV replication may be accompanied by hepatitis, i.e., increases in aminotransferase levels and, in severe cases, increases in bilirubin levels, liver failure, and death can occur. Test all patients for evidence of current or prior HBV infection by measuring HBsAg and anti-HBc before initiating HCV treatment with VOSEVI. In patients with serologic evidence of HBV infection, monitor for clinical and laboratory signs of hepatitis flare or HBV reactivation during HCV treatment with VOSEVI and during post-treatment follow-up. Initiate appropriate patient management for HBV infection as clinically indicated.

5.2 Risk of Hepatic Decompensation/Failure in Patients with Evidence of Advanced Liver Disease Postmarketing cases of hepatic decompensation/failure, including those with fatal outcomes, have been reported in patients treated with HCV NS3/4A protease inhibitor-containing regimens, including treatment with VOSEVI. Reported cases occurred in patients with baseline cirrhosis with and without moderate or severe liver impairment (Child-Pugh B or C). Because these events are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure. In patients with compensated cirrhosis (Child-Pugh A) or evidence of advanced liver disease such as portal hypertension, perform hepatic laboratory testing as clinically indicated; and monitor for signs and symptoms of hepatic decompensation such as the presence of jaundice, ascites, hepatic encephalopathy, and variceal hemorrhage. Discontinue VOSEVI in patients who develop evidence of hepatic decompensation/failure. VOSEVI is not recommended in patients with moderate to severe hepatic impairment (Child-Pugh B or C) or those with any history of prior hepatic decompensation <span class="opacity-50 text-xs">[see Dosage and Administration (2.4) , Adverse Reactions (6.2) , Use in Specific Populations (8.7) , and Clinical Pharmacology (12.3) ]</span> .

5.3 Serious Symptomatic Bradycardia When Coadministered with Amiodarone Postmarketing cases of symptomatic bradycardia and cases requiring pacemaker intervention have been reported when amiodarone is coadministered with a sofosbuvir-containing regimen. A fatal cardiac arrest was reported in a patient taking amiodarone who was coadministered a sofosbuvir-containing regimen (HARVONI ® (ledipasvir/sofosbuvir)). Bradycardia has generally occurred within hours to days, but cases have been observed up to 2 weeks after initiating HCV treatment. Patients also taking beta blockers, or those with underlying cardiac comorbidities and/or advanced liver disease may be at increased risk for symptomatic bradycardia with coadministration of amiodarone. Bradycardia generally resolved after discontinuation of HCV treatment. The mechanism for this effect is unknown. Coadministration of amiodarone with VOSEVI is not recommended. For patients taking amiodarone who have no other alternative viable treatment options and who will be coadministered VOSEVI: Counsel patients about the risk of symptomatic bradycardia. Cardiac monitoring in an in-patient setting for the first 48 hours of coadministration is recommended, after which outpatient or self-monitoring of the heart rate should occur on a daily basis through at least the first 2 weeks of treatment. Patients who are taking VOSEVI who need to start amiodarone therapy due to no other alternative viable treatment options should undergo similar cardiac monitoring as outlined above. Due to amiodarone&apos;s long half-life, patients discontinuing amiodarone just prior to starting VOSEVI should also undergo similar cardiac monitoring as outlined above. Patients who develop signs or symptoms of bradycardia should seek medical evaluation immediately. Symptoms may include near-fainting or fainting, dizziness or lightheadedness, malaise, weakness, excessive tiredness, shortness of breath, chest pains, confusion, or memory problems <span class="opacity-50 text-xs">[see Adverse Reactions (6.2) and Drug Interactions (7.3) ]</span>.

5.4 Risk of Reduced Therapeutic Effect Due to Concomitant Use of VOSEVI with Inducers of P-gp and/or Moderate to Strong Inducers of CYP Drugs that are inducers of P-gp and/or moderate to strong inducers of CYP2B6, CYP2C8, or CYP3A4 (e.g., St. John&apos;s wort, carbamazepine) may significantly decrease plasma concentrations of sofosbuvir, velpatasvir, and/or voxilaprevir, leading to potentially reduced therapeutic effect of VOSEVI. The use of these agents with VOSEVI is not recommended <span class="opacity-50 text-xs">[see Drug Interactions (7.3) ]</span>.

INTERACTIONS P-gp inducers and/or moderate to strong CYP inducers (e.g., St. John's wort, carbamazepine): May decrease concentrations of sofosbuvir, velpatasvir, and/or voxilaprevir. Use of VOSEVI with P-gp inducers and/or moderate to strong CYP inducers is not recommended. ( 5.4 , 7 ) Consult the full prescribing information prior to use for potential drug interactions. ( 4 , 5.3 , 5.4 , 7 ) Clearance of HCV infection with direct acting antivirals may lead to changes in hepatic function, which may impact safe and effective use of concomitant medications. Frequent monitoring of relevant laboratory parameters (INR or blood glucose) and dose adjustments of certain concomitant medications may be necessary. ( 7.3 )

7.1 Potential for Other Drugs to Affect VOSEVI Sofosbuvir, velpatasvir, and voxilaprevir are substrates of drug transporters P-gp and BCRP while GS-331007 (predominant circulating metabolite of sofosbuvir) is not. Voxilaprevir is also a substrate of OATP1B1 and OATP1B3. In vitro, slow metabolic turnover of velpatasvir by CYP2B6, CYP2C8, and CYP3A4 and of voxilaprevir by CYP1A2, CYP2C8, and primarily CYP3A4 was observed. Drugs that are inducers of P-gp and/or moderate to strong inducers of CYP2B6, CYP2C8, or CYP3A4 (e.g., St. John&apos;s wort, carbamazepine) may significantly decrease plasma concentrations of sofosbuvir, velpatasvir, and/or voxilaprevir leading to reduced therapeutic effect of VOSEVI. The use of these agents with VOSEVI is not recommended <span class="opacity-50 text-xs">[see Warnings and Precautions (5.4) and Clinical Pharmacology (12.3) ]</span>. VOSEVI may be coadministered with P-gp, BCRP, and CYP inhibitors. The use of OATP inhibitors which may substantially increase exposure of voxilaprevir (e.g., cyclosporine) with VOSEVI is not recommended <span class="opacity-50 text-xs">[see Clinical Pharmacology (12.3) ]</span>.

7.2 Potential for VOSEVI to Affect Other Drugs Velpatasvir and voxilaprevir are inhibitors of drug transporters P-gp, BCRP, OATP1B1, and OATP1B3. Velpatasvir is also an inhibitor of OATP2B1. Coadministration of VOSEVI with drugs that are substrates of these transporters may alter the exposure of such drugs. Coadministration of VOSEVI with BCRP substrates (e.g., methotrexate, mitoxantrone, imatinib, irinotecan, lapatinib, rosuvastatin, sulfasalazine, topotecan) is not recommended <span class="opacity-50 text-xs">[see Clinical Pharmacology (12.3) ]</span>.

7.3 Established and Potentially Significant Drug Interactions Clearance of HCV infection with direct acting antivirals may lead to changes in hepatic function, which may impact the safe and effective use of concomitant medications. For example, altered blood glucose control resulting in serious symptomatic hypoglycemia has been reported in diabetic patients in postmarketing case reports and published epidemiological studies. Management of hypoglycemia in these cases required either discontinuation or dose modification of concomitant medications used for diabetes treatment. Frequent monitoring of relevant laboratory parameters (e.g., International Normalized Ratio [INR] in patients taking warfarin, blood glucose levels in diabetic patients) or drug concentrations of concomitant medications such as cytochrome P450 substrates with a narrow therapeutic index (e.g., certain immunosuppressants) is recommended to ensure safe and effective use. Dose adjustments of concomitant medications may be necessary.

Table

3 provides a listing of established or potentially clinically significant drug interactions. The drug interactions described are based on studies conducted with either VOSEVI, the components of VOSEVI (sofosbuvir, velpatasvir, and/or voxilaprevir), or are predicted drug interactions that may occur with VOSEVI [see Contraindications (4) , Warnings and Precautions (5.3 , 5.4) , and Clinical Pharmacology (12.3) ].

Table

3 Potentially Significant Drug Interactions: Alteration in Dose or Regimen May Be Recommended Based on Drug Interaction Studies or Predicted Interaction This table is not all inclusive.

Concomitant Drug

Class: Drug Name Effect on Concentration ↓ = decrease, ↑ = increase.

Clinical Effect/Recommendation

Acid Reducing Agents: ↓ velpatasvir Velpatasvir solubility decreases as pH increases. Drugs that increase gastric pH are expected to decrease concentration of velpatasvir. Antacids (e.g., aluminum and magnesium hydroxide) Separate antacid and VOSEVI administration by 4 hours. H 2 -receptor antagonists (e.g., famotidine) These interactions have been studied in healthy adults. H 2 -receptor antagonists may be administered simultaneously with or staggered from VOSEVI at a dose that does not exceed doses comparable with famotidine 40 mg twice daily. Proton-pump inhibitors (e.g., omeprazole)

Omeprazole

20 mg can be administered with VOSEVI. Use with other proton pump-inhibitors has not been studied. Antiarrhythmics: amiodarone Effect on amiodarone, sofosbuvir, velpatasvir, and voxilaprevir concentrations unknown Coadministration of amiodarone with VOSEVI may result in serious symptomatic bradycardia. The mechanism of this effect is unknown. Coadministration of amiodarone with VOSEVI is not recommended; if coadministration is required, cardiac monitoring is recommended [see Warnings and Precautions (5.3) ]. digoxin ↑ digoxin Therapeutic concentration monitoring of digoxin is recommended when coadministered with VOSEVI. Refer to digoxin prescribing information for monitoring and dose modification recommendations for concentration increases with unclear magnitude. Anticoagulants: dabigatran etexilate ↑ dabigatran Clinical monitoring of dabigatran is recommended when coadministered with VOSEVI. Refer to dabigatran etexilate prescribing information for dose modification recommendations in the setting of moderate renal impairment. Anticonvulsants: carbamazepine phenytoin phenobarbital ↓ sofosbuvir ↓ velpatasvir ↓ voxilaprevir Coadministration is not recommended. Antimycobacterials: rifampin ↓ sofosbuvir ↓ velpatasvir ↑ voxilaprevir (single dose) ↓ voxilaprevir (multiple dose) Coadministration with rifampin is contraindicated [see Contraindications (4) ]. rifabutin rifapentine ↓ sofosbuvir ↓ velpatasvir ↓ voxilaprevir Coadministration is not recommended. Antiretrovirals: atazanavir lopinavir ↑ voxilaprevir Coadministration of VOSEVI with atazanavir- or lopinavir-containing regimens is not recommended. tipranavir/ritonavir ↓ sofosbuvir ↓ velpatasvir Coadministration is not recommended. The effect on voxilaprevir is unknown. efavirenz ↓ velpatasvir ↓ voxilaprevir Coadministration of VOSEVI with efavirenz-containing regimens is not recommended. tenofovir disoproxil fumarate (tenofovir DF) ↑ tenofovir Monitor for tenofovir-associated adverse reactions in patients receiving VOSEVI concomitantly with a regimen containing tenofovir DF. Refer to the prescribing information of the tenofovir DF-containing product for recommendations on renal monitoring.

Herbal

Supplements: St. John's wort ↓ sofosbuvir ↓ velpatasvir ↓ voxilaprevir Coadministration is not recommended. HMG-CoA Reductase Inhibitors: pravastatin ↑ pravastatin Coadministration of VOSEVI with pravastatin has been shown to increase the concentration of pravastatin, which is associated with increased risk of myopathy, including rhabdomyolysis. Pravastatin may be administered with VOSEVI at a dose that does not exceed pravastatin 40 mg. rosuvastatin ↑ rosuvastatin Coadministration of VOSEVI with rosuvastatin may significantly increase the concentration of rosuvastatin which is associated with increased risk of myopathy, including rhabdomyolysis. Coadministration of VOSEVI with rosuvastatin is not recommended. pitavastatin ↑ pitavastatin Coadministration with VOSEVI may increase the concentration of pitavastatin and is not recommended, due to an increased risk of myopathy, including rhabdomyolysis. atorvastatin fluvastatin lovastatin simvastatin ↑ atorvastatin ↑ fluvastatin ↑ lovastatin ↑ simvastatin Coadministration with VOSEVI may increase the concentrations of atorvastatin, fluvastatin, lovastatin, and simvastatin. Increased statin concentrations may increase the risk of myopathy, including rhabdomyolysis. Use the lowest approved statin dose. If higher doses are needed, use the lowest necessary statin dose based on a risk/benefit assessment. Immunosuppressants: cyclosporine ↑ voxilaprevir Coadministration of voxilaprevir with cyclosporine has been shown to substantially increase the plasma concentration of voxilaprevir, the safety of which has not been established. Coadministration of VOSEVI with cyclosporine is not recommended.

7.4 Drugs without Clinically Significant Interactions with VOSEVI Based on drug interaction studies conducted with the components of VOSEVI (sofosbuvir, velpatasvir, and/or voxilaprevir) or VOSEVI, no clinically significant drug interactions have been observed with the following drugs <span class="opacity-50 text-xs">[see Clinical Pharmacology (12.3) ]</span>: VOSEVI: cobicistat, darunavir, elvitegravir, emtricitabine, ethinyl estradiol/norgestimate, gemfibrozil, rilpivirine, ritonavir, tenofovir alafenamide, voriconazole Sofosbuvir/velpatasvir: dolutegravir, ketoconazole, raltegravir Sofosbuvir: methadone, tacrolimus